"The maintenance of a criminal justice system of which we can be proud depends on a sensible resolution," he said.

A spokesman for the MoJ insisted that legal aid remained available for very high cost cases and that advocates were in a position to give representation.

However, he said: "We have one of the most expensive legal aid systems in the world and we have to address this."

The spokesman added that the MoJ was "entirely supportive" of the self-employed Bar and had made "strenuous efforts" to secure their cooperation.

Sir Brian Leveson said the industry needed the best possible advocates to ensure trials were fair, efficient and avoided potential miscarriages of justice.

It was critical that there remained a "thriving cadre of advocates" capable of undertaking all types of publicly-funded work, he added.

Image caption
Justice Secretary Chris Grayling and the MoJ are urged to work with barristers to end the row

In May at Southwark Crown Court, Judge Anthony Leonard QC stopped the prosecution of the five men accused of a massive land-related scam after hearing that no senior barristers would take on the case.

Mr Cameron, who worked on the bid to halt the trial free of charge, argued the controversial MoJ reforms involving cuts to legal aid would prevent the defendants finding barristers of "sufficient competence".

Judge Leonard said at the time of his ruling to halt the trial that the defence had made "very substantial... but unsuccessful" efforts to find barristers to fight the defendants' case.

Analysis

By Clive Coleman, BBC legal correspondent

Image copyrightReuters

Today's ruling solves an immediate problem by re-starting one particular criminal case, but doesn't solve the bitter dispute between barristers and the Ministry of Justice, and the wider and far more serious problem of whether the most complex criminal trials can take place in future.

The reason is that following the government's 30% cut in barristers' fees in these so-called "very high cost cases", barristers have decided that the money on offer does not represent a "proper" fee for the amount of work involved.

The official line from the Criminal Bar Association (CBA) is that any barrister is free to accept such a brief.

However, barristers at the Bar are all self-employed and they have stayed solid as a group in refusing to accept briefs in these cases.

The Ministry of Justice says that when a deal was done with the CBA over fees cuts in less complex cases, the Bar agreed to work in all cases.

Today, the Court of Appeal has given both sides a heavy nudge to make every effort to resolve the dispute.

Sir Brian Leveson said that the maintenance of a "criminal justice system of which we can be proud, depends on a sensible resolution" of the current dispute.

During the appeal, counsel for Mr Grayling said emergency measures were being pursued to ensure the government would recruit more public defenders if self-employed barristers continued to refuse to take on very high-cost cases.

'Delivery of justice'

The decision to halt the trial in May had implications for similar major prosecutions - but the Court of Appeal said on Wednesday that the judge had acted incorrectly.

In its judgement, the court said the correct course of action should have been to postpone the trial while further searches for suitable barristers continued.

Delivering Wednesday's decision, Sir Brian Leveson, president of the Queen's Bench Division, said the trial should be relisted.

He said the Court of Appeal could not and should not get involved in the row between ministers and criminal barristers over pay, but stressed it was essential advocates should be available to cover all sorts of cases.

Sir Brian Leveson said the Southwark judge had been wrong to find that there was no realistic prospect of the fraud case defendants finding competent advocates who would have sufficient time to prepare.

"We are not saying that there could not come a time when it may be appropriate to order that this indictment be stayed," he said.

"That time however remains very much in the future and problems about representation will have to be developed considerably before such an exceptional order could be justified."

Bill Waddington, chair of the Criminal Law Solicitors' Association, said Sir Brian Leveson's ruling highlighted the "chronic malaise at the heart of our justice system".

"The government must urgently enter into a constructive dialogue with the legal profession to end this cat and dog fight, and preserve the fundamental principle of equality of access to justice," he said.